Audrey Delahunty1, 2, James Nuttall1, Marc Nicolas2, Jason Brand1
1 Agriculture Victoria, Department of Economic Development, Jobs and Transport, Horsham, Vic. 3401 Email email@example.com
2 Faculty of Veterinary and Agricultural Sciences, Department of Agriculture, The University of Melbourne, Parkville, Vic. 3052
Lentil production in arable, Mediterranean-type climates is limited by unreliable rainfall and the occurrence of heat waves during the reproductive phase. Under climate change predictions, there is an expectation of increasingly drier spring conditions and an increase in the frequency of heat waves. Consequently, there is a need to improve the adaptation of lentil, which is particularly sensitive to abiotic stresses. Improved yield stability through a combination of agronomic management and capturing benefits of genetic tolerance to abiotic stress such as transient high temperature is needed. In contributing to this goal we assessed the interaction of crop-available soil water and high temperature (flat pod stage) for a range of lentil genotypes. For lentil under ambient growing temperatures and high water availability, yield increased by 39% compared with low water treatments, however, high temperature (42°C day | 25°C night) caused grain yield across contrasting water regimes to be equivalent. Evidently increased water availability did not buffer the impact of high temperature. Across three lentil genotypes, high temperature caused grain number of PBA Bolt and 73838 to be significantly reduced by 36 and 53% respectively, however, for 71457, grain number was equivalent across heat treatments, which indicates that 71457 had relatively greater stability in maintaining grain number compared with the other genotypes. Overall, water availability to lentil appeared not to mitigate the impact of high temperature, however, a variation in the response of lentil across genotypes to high temperature provides promise for increasing the yield stability of lentil using breeding solutions.